Kirsty Hughes is director of the Scottish Centre on European Relations

RECENT polls have suggested that opinion on independence versus staying in the UK is split almost 50:50. And once Boris Johnson and a possible "no-deal" Brexit are added into the mix, support for independence moves into the lead.

The political dynamics here are, though, complex. Different Brexit scenarios still loom – no deal, deal or no Brexit (and perhaps another Article 50 extension). And if Brexit does go ahead with a deal (which would essentially be May’s deal), then a whole new future trade and security relationship would still need to be negotiated with the EU. How these different scenarios could impact on support for – and policies for – independence is a central and open question.

The independence debate has heated up more recently, with First Minister Nicola Sturgeon expressing a preference for another referendum by the end of next year and publishing a framework bill on holding future referendums at the end of May. But many of the issues that would become centre stage in another independence referendum – the currency, borders and trade – depend not only on where the UK goes on Brexit but also on likely EU conditions for an independent Scotland to join the EU. And once a substantive debate takes off on these issues, then public opinion will surely change again – on which direction, time will tell.

What The Polls Tell Us

Recent polls show a small increase in support for independence. The Panelbase/Sunday Times poll at the end of June had 51% No to 49% Yes (where in April it was 53% No to 47% Yes). YouGov in April also had 51% No to 49% Yes – compared to 55% No to 45% Yes last June (2018).

These polls also show the continuation of the tendency for younger people to be more in favour of independence (and indeed of remaining in the EU). The June Panelbase poll has 73% of young men (age 16-year-old to 34-year-old) supporting Yes and 58% of young women (with the latter, the strongest pro-EU group at 87% Remain in April). The 35-year-old to 54-year-old group has a small majority for No (52% men, 53% women) and the 55-year-old plus group are much more strongly pro-Union. YouGov’s April poll breaks these age groups down differently with 61% of their 25-year-old to 49-year-old group supporting independence – and the 65-year-old plus group being 73% pro-Union.

The Brexit Effect

As John Curtice has argued, the increase in support for independence in these polls is closely linked to Brexit, with a number of Remain voters shifting to support independence. In the April Panelbase poll, voters are 66% pro-Remain. There is also a strong differentiation between 2016 Remain voters who are now 56% Yes to leave voters at 34% Yes. This also indicates there is still a strong group of "Yes leavers" but they are a smaller proportion of SNP voters – with 80% of SNP voters in 2017 now identifying themselves as Remain supporters.

Add in different Brexit and Boris Johnson scenarios and the numbers start to shift more. Particularly striking is that when asked what would be better for Scotland, independence or staying in the UK under a no-deal Brexit, 59% choose independence over 41% choosing No Deal in the UK (with no change in this result from November to April). Yet when voters are asked how they would vote faced with a no-deal Brexit, the majority for independence is smaller at 52% Yes and 48% No. So a no-deal Brexit shifts the dial on independence but the "best for Scotland" question suggests there may be the potential for this to move more dramatically (depending what is driving the difference in the answers to these two questions).

Voters in the April Panelbase survey also choose independence by 51% to 49% if there is Brexit with a deal (presumably a May-style deal but this isn’t specified in the question). This is actually lower (in April) than last November when 53% chose independence in the case of a negotiated Brexit result.

The numbers also shift significantly (in the June poll) when voters are asked their view on independence if Boris Johnson becomes prime minister, with support for independence hitting 53% Yes in that case.

Looking to the future five to 30 years out, there’s a range of views of how likely Scottish independence is. The largest group – 43% (excluding "don’t knows") – think Scotland will be independent in the next 5-10 years, another 21% think this will be the case in the next 10-15 years, and a group of 10% think in 20-30 years, with 27% thinking Scotland will not become independent. So 74% think within five to 30 years, Scotland will be independent.

One last interesting shift in the recent polls is that there is now more appetite – in the Brexit context – for another independence referendum in the near future. A small majority of 51% think there should be another vote either while the UK is negotiating to leave the EU or once it has finished negotiating. If Boris Johnson as prime minister sticks to his plan of taking the UK out of the EU – deal or no deal – by October 31, that suggests support in Scotland for an early independence referendum in that scenario.

The EU, Brexit and Scotland

How the political dynamics of Brexit, of UK politics and of the Scottish independence debate unfold in the coming months is an open question. Boris Johnson looks likely to be prime minister but his threats of a no-deal Brexit by the end of October are quite likely bluster (even if his Brexiter allies take them seriously and while the risk of no deal cannot be ruled out).

But Brexit with a deal means a tweak to the political declaration, not to the Withdrawal Agreement which the EU27 have been clear they will not change. Any tweaks to the accompanying political declaration, to suit Johnson and his hard Brexit friends, might, for instance, emphasise that the final UK-EU relationship will not be a customs union. But if the Irish backstop, as a central part of the Withdrawal Agreement, remains, then this does indeed imply a customs union – unless and until the illusory and elusive "alternative arrangements" for the Irish border are found. So whether any such tweaks will get through Westminster must remain doubtful.

If Johnson doesn’t have the stomach for no deal and can’t get May’s deal (in effect) through Westminster then a General Election may soon be on us. How that pans out would be key both for a potential second EU referendum and for a second independence referendum (not least if the SNP ended up holding the balance of power at Westminster).

But all this is not just a Scottish-UK debate. If an independent Scotland aims to be in the European Union, while the rest of the UK (rUK) potentially leaves, there are various ramifications for key issues in the independence debate. A no-deal Brexit not only means chaos and a range of economic, social and political impacts, it also means hard borders between the UK and EU, including in Ireland. A Withdrawal Agreement Brexit implies a cushion of remaining in the EU’s single market and customs union until a new relationship is agreed, with any future deal likely to effectively include a customs union. But a customs union Brexit would still mean borders and barriers (both tariff and regulatory barriers) between Britain and the EU, including across the Irish Sea.

So an independent Scotland in the EU – in the face of Brexit – will mean there are some tough debates to be had about the nature of border checks at the English-Scottish border (and about the dynamic economic effects of EU membership in that scenario). This is not, however, the harder independence line that Gordon Brown recently claimed it to be. This is, rather, a direct impact of Brexit (there currently being no separate UK rather than EU customs union or single market).

Currency also comes in here. While polls suggest Scottish voters prefer staying with the pound sterling in the short term or longer, the SNP’s policy is now to have a separate Scottish currency as soon as possible (though the Growth Commission suggests "soon" could be in 10 years' time). But keeping the pound for an indeterminate period, while the UK leaves the EU, may prove a stumbling block for Scottish EU accession. Member states outside the euro must show they have a monetary policy promoting price stability and must treat exchange rates as a matter of common concern – tricky to do if the Bank of England is determining these things. If the SNP’s currency stance risks its pro-EU stance, how will that impact on voters’ preferences – something may have to give.

How the independence debate will develop, and how support for independence will change, as, when and if Brexit actually happens, and as issues like borders and currency and their link to EU membership become clearer, is for now an open question. A no-deal Brexit – and the ensuing chaos it would provoke – would surely, as the polls above suggest, strengthen support for independence, but border concerns would also be trickier to assuage. How rapidly opinion changes, in a no-deal scenario, would then also be likely to impact on political choices made by the Scottish government. There’s little chance of a unilateral declaration of independence in the face of a no-deal Brexit but an advisory plebiscite is being spoken of by some. An advisory referendum as a strategy to push the UK government to a deal on independence is one political possibility. But even with the UK leaving the EU, the EU will not be open to an independent Scotland in the EU that hasn’t achieved independence in a legally and constitutionally sound way (though in the chaos of a no-deal Brexit, unexpected political developments are more likely than not in both the UK and Scotland).

While support for independence and staying in the UK is more balanced in the face of a possible Brexit with a deal, the reality of Brexit happening – and the cushion of a transition period in the single market – could move opinion in different directions.

The relative calm of transition could reassure some that Brexit with a deal and staying in the UK is ok. But for others, the reality of Brexit could point in the other direction – increasing support for independence. Moreover, the chances of Scotland staying relatively seamlessly in the single market and perhaps the customs union, would depend on an independence vote happening sufficiently ahead of the end of the Brexit transition, to allow for an independent Scotland to resolve its own transitional relationship with the EU once independent.

And if, as is still possible, the UK never leaves the EU – perhaps holding a People’s Vote with voters choosing Remain (in line with current polls) – then maybe the Scottish independence debate will become calmer. But UK politics even with no Brexit will not return to where it was four years ago. English nationalism and populism will divide and distort English politics for years to come. Where Scottish politics and independence goes in the face of no Brexit is one more open question. Independence, after all, would be much more straightforward to manage if the UK remains in the EU.

Overall, in the three years since the Brexit vote, Scottish politics has seemed in many ways to be in a holding pattern. But as Brexit politics takes off again, after the bizarre and troubling interregnum of the Tory leadership contest, Scottish political dynamics look like taking off too.